Our instance of Discourse has a plugin installed that allows the original poster (OP) on a topic to mark the topic as solved. When you post a topic, you’ll see a gray checkmark in responses. If one of the responses solved your problem, you can select this and your topic will be marked “solved.” This will be helpful for people who scan the list for recent topics that are still unsolved as they can potentially skim or skip topics that are already resolved.
Give it a try, even on some of your past posts.